Transliteration: gza' gtad
<noun> "Vacillatory focus", "rationalized uncertainties". A special term which only occurs in secret mantra vajra vehicle, in ཕྱག་རྒྱ་ཆེན་པོ་ Mahāmudrā and རྫོགས་པ་ཆེན་པོ་ Great Completion. It means having a གཏད་སོ་ point of focus of the intellect which is one possibility of a pair of opposites which are being argued back and forth internally and which one is thus གཟའ་ vacillating over.The term is used to explain a particular type of fault that occurs in attempting to meditate on non-dualistic mind as shown in the two systems mentioned above. In these systems, when meditating on non-dualistic mind, the practitioner is meant to drop conceptual mind altogether. However, what happens to most meditators, at least to begin with, is that they can't quite drop conceptual mind and the conceptual mind runs in a pattern of doubt, ཐེ་ཚོམ་ which thinks, "is this the essence of mind? Yes, it is! No, it isn't". In that case, there is a "focus" of conceptual mind and that mind is "vacillating" between the two opposites of "It's this! No, it's that!"
The term thus is twice pejorative. The word "vacillatory" refers to a process of hovering around a subject, seeing it from this angle and that angle because of being uncertain of which way it really is; i.e., vacillating over which way it is. "Focus" means that rational-mind takes one of the possible angles and settles on that. For example, in the process of resting in the essence of mind, there can be the fault of not leaving rational mind but staying within in it and thinking, "Yes, this is the essence of mind" or "No, this is not it. It is that". Each of those is a vacillatory focus. Any vacillatory focus implies that the practitioner has not left བློ་ rational-mind and so is not in non-dualistic mind.
E.g., in [FEG] དེའི་ཚེ་ན་སེམས་འདི་ཡིན་གྱི་གཟའ་གཏད་ཐམས་ཅད་དང་བྲལ་བ་ནི་ "At that point, being free from every vacillatory focus such as "Mind is this"...".